Hack to make sure even (extra)subsectors without planepolys have segs adjusted

this fixes a crash in (old) GFZ2 at the ramp as a result of creating pv1/pv2. This probably means before pv1/pv2 there could have been some silly typecasting from vertex_t to polyvertex_t to get fixed vertex coords and such...

src/hardware/hw_bsp.c

@@ -878,8 +878,8 @@ static void AdjustSegs(void)
 		count = subsectors[i].numlines;
 		lseg = &segs[subsectors[i].firstline];
 		p = extrasubsectors[i].planepoly;
-		if (!p)
-			continue;
+		//if (!p)
+			//continue;
 		for (; count--; lseg++)
 		{
 			float distv1,distv2,tmp;
@@ -892,27 +892,29 @@ static void AdjustSegs(void)
 				continue;
 #endif
 
-			for (j = 0; j < p->numpts; j++)
-			{
-				distv1 = p->pts[j].x - FIXED_TO_FLOAT(lseg->v1->x);
-				tmp    = p->pts[j].y - FIXED_TO_FLOAT(lseg->v1->y);
-				distv1 = distv1*distv1+tmp*tmp;
-				if (distv1 <= nearv1)
-				{
-					v1found = j;
-					nearv1 = distv1;
-				}
-				// the same with v2
-				distv2 = p->pts[j].x - FIXED_TO_FLOAT(lseg->v2->x);
-				tmp    = p->pts[j].y - FIXED_TO_FLOAT(lseg->v2->y);
-				distv2 = distv2*distv2+tmp*tmp;
-				if (distv2 <= nearv2)
+			if (p) {
+				for (j = 0; j < p->numpts; j++)
 				{
-					v2found = j;
-					nearv2 = distv2;
+					distv1 = p->pts[j].x - FIXED_TO_FLOAT(lseg->v1->x);
+					tmp    = p->pts[j].y - FIXED_TO_FLOAT(lseg->v1->y);
+					distv1 = distv1*distv1+tmp*tmp;
+					if (distv1 <= nearv1)
+					{
+						v1found = j;
+						nearv1 = distv1;
+					}
+					// the same with v2
+					distv2 = p->pts[j].x - FIXED_TO_FLOAT(lseg->v2->x);
+					tmp    = p->pts[j].y - FIXED_TO_FLOAT(lseg->v2->y);
+					distv2 = distv2*distv2+tmp*tmp;
+					if (distv2 <= nearv2)
+					{
+						v2found = j;
+						nearv2 = distv2;
+					}
 				}
 			}
-			if (nearv1 <= NEARDIST*NEARDIST)
+			if (p && nearv1 <= NEARDIST*NEARDIST)
 				// share vertice with segs
 				lseg->pv1 = &(p->pts[v1found]);
 			else
@@ -927,7 +929,7 @@ static void AdjustSegs(void)
 				pv->y = FIXED_TO_FLOAT(lseg->v1->y);
 				lseg->pv1 = pv;
 			}
-			if (nearv2 <= NEARDIST*NEARDIST)
+			if (p && nearv2 <= NEARDIST*NEARDIST)
 				lseg->pv2 = &(p->pts[v2found]);
 			else
 			{